Sikorsky, Lord Test Helicopter Vibration Suppressor

Sikorsky and Lord completed flight-testing a hub-mounted vibration suppressor (HMVS) in March, the companies said yesterday.

The system seeks to address crew fatigue and reduced equipment reliability caused by helicopter vibration. The HMVS testbed was a UH-60A Black Hawk, which accelerated from a hover to 150 knots, performed autorotations and made turns with 60 degrees of bank.

The two companies collaborated on the evaluation at the U.S. Army’s Aviation Applied Technology Directorate at Fort Eustis, Va. The HMVS system cancels the largest vibratory loads near the source of the vibration–the main rotor hub–thus keeping the loads from propagating into the airframe.

In preliminary flight-testing, the HMVS–weighing 30 percent less than current passive systems–was found to reduce vibration “significantly.” A schedule announced in 2011 called for the equipped Black Hawk to fly that year or in 2012, with a plan eventually to integrate an HMVS into all Sikorsky helicopters.